Silica spherical particles for semiconductor sealing material

Abstract

The purpose of the present invention is to provide: silica particles of which the maximum particle diameter can be minimized and which can achieve proper fluidability that cannot be achieved by the conventional techniques; and silica spherical particles which, when used as a filler for a heat-dissipating sheet, can achieve excellent heat conductivity and flexibility. Silica spherical particles characterized in that, when particles each having a size of 5 μm or more and imaged by an optical measurement are observed, the particle diameter of each of the particles, which is determined from the image, satisfies the following requirements. Requirements: D99≤29 μm, and 10 μm≤Dmode<D99, and D99 / Dmode≤1.5, and Dmode≤20 μm.

Description

TECHNICAL FIELD[0001]The present invention relates to silica spherical particles used for a semiconductor sealing material.BACKGROUND ART[0002]In recent years, semiconductor packages have become increasingly smaller and thinner. Particularly, in applications typified by smartphones, flip-chip connections that can be made thinner by multi-pins with a larger number of pins have been widely used, instead of conventional wire bonding. Flip-chip connection connects electrodes on a silicon chip and a substrate via minute solder balls, and has an advantage of saving space as compared with the conventional wire bonding portion. On the other hand, as the number of pins increases, a distance between adjacent solder balls becomes narrower, and a gap between the silicon chip and the substrate becomes narrower year by year (see Non-Patent Document 1). In the past, when such a narrow gap is sealed, sealing was performed with a resin alone without being filled with a filler. In such a case, it is ...

AI Technical Summary

Benefits of technology

The present invention relates to a new type of silica particles that have a small maximum particle diameter and achieve optimal fluidity, making them ideal for use as sealing materials for semiconductors and other electronic components. The silica particles have been tested using both a flow tester method and a rheometer method, with the results showing that they have a high discharge rate and smooth fluidity at the gate portion of the mold. The fluidity in the region where the shear rate is slow should be kept within a proper range to prevent voids from occurring. The heat dissipating sheet produced using the present invention has excellent flexibility and can achieve high thermal conductivity by increasing the filler ratio.

Problems solved by technology

In such a case, it is necessary to seal separately with a resin different from the resin for the overfill, which causes a problem that the productivity and the cost are greatly compromized.

In order to obtain a sufficient heat dissipation effect, the heat-dissipating sheet is required to be flexible enough to fill the gap generated by the surface roughness of the heating element and the heat dissipating component, since this gap will greatly impair the heat dissipation effect.

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